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Antitubercular Agent/Discontinued

POTASSIUM AMINOSALICYLATE

POTASSIUM AMINOSALICYLATE

Clinical safety rating

caution

Comprehensive clinical and safety monograph for POTASSIUM AMINOSALICYLATE (POTASSIUM AMINOSALICYLATE).


What is POTASSIUM AMINOSALICYLATE?

Comprehensive clinical and safety monograph for POTASSIUM AMINOSALICYLATE (POTASSIUM AMINOSALICYLATE).

Indications & Uses

Adjunctive treatment of tuberculosis (as second-line agent)Off-label: treatment of ulcerative colitis (as mesalamine prodrug)

Compare POTASSIUM AMINOSALICYLATE vs CAPREOMYCIN SULFATE →View all Antitubercular Agent drugs →

Mechanism of Action

Exact mechanism unknown; may competitively inhibit folic acid synthesis and/or disrupt mycobacterial cell wall metabolism via inhibition of salicylate hydroxylation.

What the body does with it

MetabolismHepatic (acetylation to N-acetyl-4-aminosalicylic acid and other metabolites); also undergoes intestinal metabolism by gut bacteria.
ExcretionRenal: >80% as metabolites (acetyl, glycolyl conjugates) and unchanged drug; fecal: <5%.
Half-life0.5-1.5 hours for parent drug; acetylated metabolite half-life 2-3 hours; accumulation occurs in renal impairment.
Protein binding50-60% bound to albumin.
Volume of Distribution0.2-0.4 L/kg; reflects distribution into total body water with limited tissue penetration.
BioavailabilityOral: ~90% absorbed; food may delay absorption.
Onset of ActionOral: 2-4 weeks for bacteriostatic effect in tuberculosis; topical: not applicable.
Duration of ActionDosing every 6-8 hours required due to rapid elimination; sustained effect requires consistent serum levels.
Molecular Weight191.3

Classification & Brands

Dosing & administration

Adults: 4 g (as granules or powder) orally twice daily, equivalent to 8 g/day of aminosalicylic acid base.

Dosage formPOWDER
Renal impairmentGFR <50 mL/min: not recommended due to risk of accumulation; if unavoidable, reduce dose to 4 g once daily. GFR <30 mL/min: avoid use.
Liver impairmentChild-Pugh Class A: no adjustment. Child-Pugh Class B: reduce dose by 50% (to 2 g twice daily). Child-Pugh Class C: avoid use.
Pediatric useChildren: 200-300 mg aminosalicylic acid base per kg body weight per day, divided into 2 doses. Maximum 8 g/day.
Geriatric useStart at lower end of dosing (4 g once daily) due to potential decreased renal function and increased risk of gastrointestinal intolerance.

Use during pregnancy

1st trimesterInsufficient human data; animal studies not available. Use only if clearly needed.
2nd trimesterLimited data; no known teratogenic effects reported. Use only if benefit justifies risk.
3rd trimesterAvoid near term due to potential for methemoglobinemia and hemolytic anemia in newborn.

Clinical note

Comprehensive clinical and safety monograph for POTASSIUM AMINOSALICYLATE (POTASSIUM AMINOSALICYLATE).

Placental transferCrosses placenta; fetal serum concentrations approximate maternal levels.
BreastfeedingMinimal excretion into breast milk; levels considered low. Monitor infant for diarrhea or rash. Avoid in G6PD deficiency.
Lactation RatingL3 - Moderately Safe
Teratogenic RiskFirst trimester: Insufficient data; no known human teratogenicity but animal studies inconclusive. Second/third trimester: No documented fetal harm; use only if clearly needed.
Fetal MonitoringMonitor serum potassium levels, renal function, and signs of GI intolerance. For fetus: ultrasound for growth and amniotic fluid volume.
Fertility EffectsNo known effects on fertility in human studies.

Warnings & precautions

■ FDA Black Box Warning

No FDA black box warning.

Side Effect Profile

Serious Effects

Absolute Contraindications

Hypersensitivity to aminosalicylatesSevere renal impairment (CrCl <30 mL/min)G6PD deficiency

Clinical Precautions

PrecautionsHypersensitivity reactions including fever and rash, Hepatotoxicity (discontinue if jaundice or liver enzyme elevation occurs), Renal impairment may require dose adjustment, Gastrointestinal intolerance, May cause hypocalcemia and hypokalemia, Interference with thyroid function tests
Food/DietaryAvoid alcohol. Take with food or milk to reduce gastrointestinal irritation. Avoid large amounts of high-potassium foods (e.g., bananas, oranges, potatoes) unless directed by a physician, as this drug may alter potassium levels. No specific food restrictions beyond these.

Clinical Tips & Counseling

Clinical PearlsMonitor for hepatotoxicity, including elevated liver enzymes and bilirubin, especially in the first 3 months of therapy. Administer with food to reduce GI upset. Concurrent use with rifampin may decrease rifampin levels; separate doses by 8-12 hours. Contraindicated in severe renal impairment (CrCl < 30 mL/min) due to risk of hypokalemia and salicylate toxicity. Hypersensitivity reactions including fever, rash, and eosinophilia may occur; discontinue if severe.
Patient AdviceTake this medication with food or milk to prevent stomach upset. · Do not take antacids containing aluminum or magnesium within 3 hours of this medication. · Avoid alcohol while taking this medication due to increased risk of liver damage. · Report any signs of liver problems (yellowing skin or eyes, dark urine, abdominal pain) to your doctor immediately. · Use effective contraception during treatment as this drug may harm an unborn baby. · Do not stop taking this medication without consulting your doctor, even if you feel better. · Keep all appointments for blood tests to monitor liver function and potassium levels.

POTASSIUM AMINOSALICYLATE Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

CAPREOMYCIN SULFATEINHMYAMBUTOLNYDRAZIDP.A.S. SODIUM

External sources

DailyMed (NIH) PubMed OpenFDA